Boiler



J. H. FOX

March 21, 1933.

BOILER Filed Feb. 16 1931 INVENTOR @Ms /1/ /CEX ATToRNEY Patented Mar. 21, 1933 UNITED STATES JoNAs H. Fox, or SEATTLE, WASHINGTON:

IBOILZEB Application led February 16,1931.. Serial-No. 516,672.

This invention relates to tubular boilers and has reference particularly to stationary,

low pressure steam and hot water boilers of Y a type. especially designed for heating plants as used in apartment buildings, stores, residences, etc.; this particular invention being an improvement on the construction disclosed and illustrated in my (zo-pending application filed on July 22, 1929, under Serial Number 880,020.

The above numbered application discloses a lire tube boiler in which the rear end is closed by an upper flue sheet, a lower flue sheet set forwardly thereof and a horizontal sheet that is welded at one edge, to the bottom edge of the upper flue sheet, and is likewise welded at another edge,rto the top edge of the bottom flue sheet. In this particular construction, the horizontal sheet is subjected to boiler pressure which tends to bow or warp it downwardly. Also, by reason of contraction and expansion of various boiler parts attached to the flue sheets, there is a resultant relative movement of these latter parts which tends to and does cause loosening of the weld- .shell and axially parallel thereto, is; a tubued joints with resultant leakage in the boiler.

In view of the above objectionable features of the. boiler as previously built, it has been the object of this invention to eliminate them by the provision of a construction in which the two flue sheets and the horizontal sheet are all formed in one integraly plate, and wherein breaking at the junction points is avoided by the merging of one part into the other through a gradual bend. Also to overcome buckling or bowing of the horizontal plate by the use of corrugations which add stiffness and rigidity and this makes it unnecessary to use supporting staybolts, or the like.

vOther objects of the invention reside in the various details of construction and com- Vbination of parts as will hereinafter be described.

In accomplishing these objects, I have proon the rearV end sheet 3. Water connections, Y

lembodying theL rfeatures of construction in accordance with the present-invention. Fig. 2 isa cross section taken substantially on the lline 2 2 inF'ig. 1.- y l Fig. 3 is asectional detail o f the flue sheet 5.5

showingthe merging of the various sections through gradually curved bends.

Referring more in detail to the several vlews of the drawing- The boiler, briey described, comprises a .horizontallyl disposed cylindrical shell 1,

closed atfits forward end by a flue sheet 2 and'closed at its rear end by a flue Ysheet com- Vprising .anupper 'section 3, a lower section 4 and anintermediate, horizontal section; 5. 55

In this. arrangement the lower section is set forwardly of the upper section and to gether with the horizontal sheet 5 andshell 1 forms; a combustion chamber 6; this cham- -ber being closed "at its. rear side. by a plate .70

'Z .attached to the shell. Harige by bolts 8.y The combustion chamber is also lined at the back vside and bottom and sides, by suitable re brick as designated at 9. V 4 y Located within the lower portion of the 12 having an opening 13 equipped with a door 14 within'which an oil burner 15 is mounted to adapt the furnace to the burning of oil. Y 85 Extending lengthwise of the boilervshell are the live tubes, there being several rows of these tubes, as vdesignated at 18a, which have their opposite ends extended through the front and rear flue sheets 2'and 3, and there; f90' is a like number of tubes designated at 18?) which extend at their forward ends through the flue sheets 2 and at their rearward ends through flue sheet 4 into the combustion chamber. The forward ends of all tubes-. 95 open intol a smoke box 20 mounted on the front end flue sheet above and at opposite sides'of the furnace. The rear ends of tubes 18a open into a stack connection 21 mounted 100 such as at 35 centrally of the base of the shell, and 36-36, at the top, are provided for intake and outlet, respectively.

The feature of the present invention re- 5 sides in the rear end flue sheet construction, the several sections of which are formed in an integral plate, rand in thisrespect it differs from the construction in the prior application. It will be observed by reference particularly to Fig. 3, that the top section 3 merges into the horizontal section through a gradually curved bend as at 40. Likewise,` the horizontal plate merges vinto the lower section 4 through a gradually curved bend 41'. This construction permits forward or rearward fiexure of the sheet incident yto eXpansion orcontraction of the shell and flues with'- out danger of breaking any connecting joints since the plate simply yields at the curved Y places to compensate forrelative movement.

The plate 5 has also been stiffened by use of corrugations formed lengthwise thereof, as shown best in Fig. 2. These corrugations are sufficient to give the required stiness to the plate so that it will not be bowed downwardly under the boiler pressure. An advantage in this corrugated construction resides in the fact that stay bolts are notreA quired and 'this permits vof a lmore practical disposition of the lire tubes.

Having thus described my invention, what I claim as new therein, and desire to vsecure by Letters-Patent, is: n l In a boiler of the character described, a yhorizontal shell, a flue sheet closing one end of theshell and. comprising upper and'lower relatively oifset sections', and a horizontal connecting section merging into the oifset sections in gradually rounded curves; said 4G horizontal section being corrugated lengthwise with the corrugations thereof merging at their ends within the rounded curves.

Signed at Seattle, King County, Washington, this 27th day of January, 1931.

y JONAS- I-I. FOX. 

